Pteleopsis myrtifolia (PROTA)
Pteleopsis myrtifolia (C.Lawson) Engl. & Diels
- Protologue: Engl., Monogr. afrik. Pflanzen.-Fam. 4: 4 (1900).
- Family: Combretaceae
- Pteleopsis stenocarpa Engl. & Diels (1900),
- Pteleopsis obovata Hutch. (1917).
- Stink-bushwillow, two-winged stinkbush (En).
- Mgoji, mlakwenzi (Sw).
Origin and geographic distribution
Pteleopsis myrtifolia occurs in Kenya, Tanzania, Malawi, Zambia, Angola, Botswana, Zimbabwe, Mozambique and north-eastern South Africa.
In Tanzania leaf sap, together with leaf sap of Diospyros zombensis (B.L.Burtt) F.White, is drunk to treat dysentery. Leaf sap is also drunk to treat threatening abortion. Roots are cooked with chicken and the soup is taken to treat sterility. A root decoction is taken to treat venereal diseases, dysentery and excessive menstruation. It is externally applied to sores.
The wood is strong and used for making furniture, building poles and tool handles. The wood is also used to make firewood and charcoal. The leaves are cooked and eaten as a vegetable; the fruits are considered edible too. The tree is sometimes used for shade, although it is slow-growing. Livestock does not browse the plant. However, in southern Tanzania, the leaves are eaten by the edible caterpillar Imbrasia lucida, which can occur in large numbers on the plant. The caterpillars are picked, not fed during one day and then fried with onions in oil. They can also be cooked and dried for later use. The flowers are much visited by bees. In South Africa the young stems are used in basketry. In Maputuland the smoke of the wood is used to preserve food.
Production and international trade
The leaves and roots of Pteleopsis myrtifolia are only sold in local markets.
From the leaves the pentacyclic triterpenoid taraxerol was isolated; it had minimal IC values of 0.04 mg/ml and 0.016 mg/ml against Escherichia coli and Enterococcus faecalis, respectively. Several of the leaf extracts also showed antibacterial activity against Escherichia coli and Enterococcus faecalis. Some of the leaf extracts inhibited the growth of cancer cell lines MCF-12A, H157, WHC03 and HeLa. A methanolic root extract showed strong antiproliferative effects against the T24 bladder cancer cells, but was less effective against the HeLa cervical cancer and MCF7 breast cancer cell lines. A root extract showed significant antifungal activity against Candida glabrata and Candida krusei, and moderate antifungal activity against Cryptococcus neoformans and several other Candida spp.
Deciduous shrub or small tree up to 10(–25) m high; wood red, very hard; bark grey or yellow-grey; crown rounded; young branchlets reddish-brown, slender, often pendulous, pubescent at first but soon almost glabrous. Leaves opposite or almost opposite; petiole up to 1 cm long, rather slender, usually short-hairy; blade elliptical to very narrowly elliptical or obovate-elliptical, up to 9.5 cm × 3.5 cm, but sometimes as small as 1 cm × 0.5 cm, dark green, shiny above, usually glabrous except for some short hairs on the midrib, apex slightly acute or rather bluntly acuminate, base cuneate, pinnately veined with 6–9 pairs of secondary veins. Inflorescence an axillary head-like raceme up to 4.5 cm long; rachis slender, glabrous or sparsely short-hairy. Flowers bisexual or functionally male in the same inflorescence, bisexual flowers at apex, regular, 5-merous, white or yellow, unpleasantly scented; pedicel short; lower receptacle c. 5 mm long, flattened, glabrous, upper receptacle 2.5–3 mm × c. 2 mm, campanulate, glabrous, joined to the lower receptacle by a slender stalk-like portion 1–2 mm long; sepals deltate; petals obovate to almost circular, 1.5–2.5 mm × 1–2 mm, glabrous; stamens 10, in 2 circles, filaments 3.5–5 mm long; ovary inferior, style 5–6 mm long. Fruit a 2–3(–4)-winged nut, 1–2.5 cm × 0.5–1.7 cm, very variable in size and shape, with up to 15 mm long stipe, apex generally emarginate, base unequal, very slender, greenish-yellow drying to pale brown, indehiscent, 1-seeded.
Other botanical information
Pteleopsis is a small genus of about 10 species, all in tropical Africa. It is intermediate in many characters between Combretum and Terminalia. Pteleopsis anisoptera (M.A.Lawson) Engl. & Diels closely resembles Pteleopsis myrtifolia, and there appears no single character that separates the two species, and it is highly probable that they hybridize.
Several other Pteleopsis species are medicinally used.
Pteleopsis hylodendron Mildbr. occurs in the forest area of West and Central Africa, and has several medicinal uses. In Cameroon a stem bark infusion is taken to treat measles, chickenpox, venereal diseases, liver and kidney problems and dropsy. In Congo leaf sap is used as a wash to treat epilepsy. In Cameroon the wood is used for railway sleepers. From the stem bark a triterpenoidal saponin bellericagenin (pteleopsoside) and the sphingolipids hylodendroside-I and hylodendroside-II were isolated, along with friedelin, β-carotene, lupeol, β-sitosterol and stigmasterol. The methanolic stem bark extract showed hepatotoxic and nephrotoxic effects in rodents.
Pteleopsis tetraptera Wickens occurs in Kenya and Tanzania. In Tanzania a root decoction is taken to treat venereal diseases. It is externally applied to snakebites. The wood is used for building poles, spoons and tool handles and also for firewood and charcoal. It is threatened by habitat loss and is listed as lower risk/near threatened in the IUCN Red List.
Growth and development
Pteleopsis myrtifolia flowers from November to April. Established trees are vulnerable to frost, but very resistant to drought.
Pteleopsis myrtifolia occurs in evergreen forest, riverine forest, Brachystegia woodland or savanna woodland, Baikiaea woodland, mopane woodland and Acacia-Combretum-Terminalia tree savanna, also on rocky hillsides and stony outcrops, from sea-level up to 1600 m altitude.
Propagation and planting
Average 1000 seed weight is 31.7 g. Often, most of the seeds are parasitized. Seeds are soaked during 12 hours before planting, and the floating, parasitized, seeds are discarded. Germination takes place between 11 and 31 days, but only 5% of the seeds usually germinates.
Pteleopsis myrtifolia has a relatively large area of distribution, and is relatively common to very common in some areas. It is therefore not threatened by genetic erosion.
The leaves and roots of Pteleopsis myrtifolia are used in traditional medicine and preliminary pharmacological research confirm these uses. More information is needed, however, concerning its toxicity because of its internal use.
- Fyhrquist, P., 2007. Traditional medicinal uses and biological activities of some plant extracts of African Combretum Loefl., Terminalia L. and Pteleopsis Engl. Species (Combretaceae). Academic dissertation. Faculty of Biosciences, Division of Plant Biology, Department of Biological and Environmental Sciences, University of Helsinki, Faculty of Pharmacy, Division of Pharmaceutical Biology, University of Helsinki and Institute for Preventive Nutrition, Medicine and Cancer, Folkhälsan Research Center, Helsinki, Finland. 183 pp.
- Kamuhabwa, A., Nshimo, C. & de Witte, P., 2000. Cytotoxicity of some medicinal plant extracts used in Tanzanian traditional medicine. Journal of Ethnopharmacology 70: 143–149.
- Lovett, J.C., Ruffo, C.K., Gereau, R.E. & Taplin, J.R.D., 2007. Field Guide to the moist forest trees of Tanzania. Frontier Publishing, United Kingdom. 303 pp.
- Neuwinger, H.D., 2000. African traditional medicine: a dictionary of plant use and applications. Medpharm Scientific, Stuttgart, Germany. 589 pp.
- Rabie, A., 2005. Bioactivity of extracts and components of Pteleopsis myrtifolia. PhD Thesis. University of Pretoria, South Africa. 205 pp.
- Barreto, L.S., 1967. Timbers of Mocambique. Wood structure. 1st series. Revista dos Estudios Gerais Universitarios de Mocambique 4: 59–183.
- Fyhrquist, P., Mwasumbi, L., Haeggstrom, C.A., Vuorela, H., Hitunen, R. & Vuorela, P., 2004. Antifungal activity of selected species of Terminalia, Pteleopsis and Combretum (Combretaceae) collected in Tanzania. Pharmaceutical Biology 42(4/5): 308–317.
- Gaugris, J.Y., van Rooyen, M.W., Bothma, J. du P. & van der Linde, M.J., 2007. Hard wood utilization in buildings of rural households of the Manquakulane community, Maputaland, South Africa. Ethnobotany Research & Applications 5: 97–114.
- Gillah, P.R., Makonda, F.B.S., Ishengoma, R.C., Shaban, Z. & Kitojo, D.H., 2007. The lesser known Pteleopsis myrtifolia timber from Tanzania: Its utilization properties, potential substitute and role in income generation of the rural poor. Journal of Tanzania Association of Foresters. Volume 11: 69–77.
- Glen, H.F., 2011. Pteleopsis myrtifolia (M.A.Lawson) Engl. & Diels. [Internet]. South African National Biodiversity Institute, Cape Town, South Africa. http://www.plantzafrica.com/plantqrs/stapelia.htm. Accessed August 2012.
- Latham, P., 2007. Plants visited by bees and other useful plants of Umalila, southern Tanzania. Third edition. P.Latham, DFID, United Kingdom. 216 pp.
- Mtengeti, E.J. & Mhelela, A., 2006. Screening of potential indigenous browse species in semi-arid central Tanzania. A case of Gairo division. Livestock Research for Rural Development 18(8). 6 pp.
- Mwavu, E.N., Friederiks, J.B. & Rulangalanga, Z.K., 2001. Nutritive value of selected forges on the coastal region rangelands of Tanzania. Makerere University Agricultural Research Institute Kampala, MUARIK Bulletin 4: 62–70.
- Newmark, W.D., 2001. Conserving biodiversity in East African forests: a study of the eastern arc mountains. Ecological Studies 155. Springer, Berlin, Germany. 197 pp.
- Wickens, G.E., 1973. Combretaceae. In: Polhill, R.M. (Editor). Flora of Tropical East Africa. Crown Agents for Oversea Governments and Administrations, London, United Kingdom. 99 pp.
- E.N. Matu, CTMDR/KEMRI, P.O. Box 54840–00200, Nairobi, Kenya
Correct citation of this article
Matu, E.N., 2013. Pteleopsis myrtifolia (M.A.Lawson) Engl. & Diels. In: Schmelzer, G.H. & Gurib-Fakim, A. (Editors). Prota 11(2): Medicinal plants/Plantes médicinales 2. PROTA, Wageningen, Netherlands. Accessed 11 April 2019.
- See this page on the Prota4U database.